A high-current, high-voltage power supply with special output current waveform for APS injector synchrotron dipole magnets

This paper describes a high-voltage, high-current power supply for the injector synchrotron dipole magnets at APS. In order to reset the dipole magnets in each cycle two different current waveforms are suggested. The first current waveform consists of three sections, namely: dc-reset, linear ramp, and recovery sections where injection is done ``on the fly``. The second current waveform consists of six different sections, dc-reset, transition to injection level, injection flat level, parabolic, linear ramp and recovery sections. The effect of such waveforms on the beam is discussed and the power supply limitations to follow such waveforms are given. The power supply limitations are due to the power components and control loops. The reference for the current loop is generated by a DAC which is discussed

Spectral action for Bianchi type-IX cosmological models

In this paper we prove a rationality phenomena for the coefficients of the heat kernel expansion of the Dirac-Laplacian of Bianchi IX cosmological models. Due the complexities arising from the anisotropic nature of the model, we present a novel method of writing the heat coefficients as Wodzicki resiudes of certain Laplacians and then provide an elegant proof of the rationality result. That is, we show that each coefficient is described by a several variable polynomial with rational coefficients of the cosmic expansion factors and their higher derivatives of a certain order. This result confirms the arithmetic nature of the complicated terms in the expansion

Ultrathin graphene-based membrane with precise molecular sieving and ultrafast solvent permeation

Graphene oxide (GO) membranes continue to attract intense interest due to their unique molecular sieving properties combined with fast permeation. However, their use is limited to aqueous solutions because GO membranes appear impermeable to organic solvents, a phenomenon not yet fully understood. Here, we report efficient and fast filtration of organic solutions through GO laminates containing smooth two-dimensional (2D) capillaries made from large (10-20 μm) flakes. Without modification of sieving characteristics, these membranes can be made exceptionally thin, down to â 1/410 nm, which translates into fast water and organic solvent permeation. We attribute organic solvent permeation and sieving properties to randomly distributed pinholes interconnected by short graphene channels with a width of 1 nm. With increasing membrane thickness, organic solvent permeation rates decay exponentially but water continues to permeate quickly, in agreement with previous reports. The potential of ultrathin GO laminates for organic solvent nanofiltration is demonstrated by showing >99.9% rejection of small molecular weight organic dyes dissolved in methanol. Our work significantly expands possibilities for the use of GO membranes in purification and filtration technologies

Effect of magnesium and vitamin B6 supplementation on mental health and quality of life in stressed healthy adults: Post‐hoc analysis of a randomised controlled trial

Magnesium status and vitamin B6 intake have been linked to mental health and/or quality of life (QoL). In an 8‐week Phase IV randomised controlled study in individuals with low magnesemia and severe/extremely severe stress but who were otherwise healthy, greater stress reduction was achieved with magnesium combined with vitamin B6 than with magnesium alone. We present a previously unreported secondary analysis of the effect of magnesium, with and without vitamin B6, on depression, anxiety, and QoL. Adults with Depression Anxiety Stress Scales (DASS‐42) stress subscale score >18 were randomised 1:1 to magnesium + vitamin B6 combination (Magne B6®; daily dose 300 and 30 mg, respectively) or magnesium alone (Magnespasmyl®; daily dose 300 mg). Outcomes included changes from baseline in DASS‐42 depression and anxiety scores, and QoL (Short Form‐36 Health Survey). DASS‐42 anxiety and depression scores significantly improved from baseline to week 8 with both treatments, particularly during the first 4 weeks. Improvement in QoL continued over 8 weeks. Participants' perceived capacity for physical activity in daily life showed greater improvement with magnesium + vitamin B6 than magnesium alone (Week 4). In conclusion, magnesium supplementation, with or without vitamin B6, could provide a meaningful clinical benefit in daily life for individuals with stress and low magnesemia

Hybrid Rational Haar Wavelet and Block Pulse Functions Method for Solving Population Growth Model and Abel Integral Equations

We use a computational method based on rational Haar wavelet for solving nonlinear fractional integro-differential equations. To this end, we apply the operational matrix of fractional integration for rational Haar wavelet. Also, to show the efficiency of the proposed method, we solve particularly population growth model and Abel integral equations and compare the numerical results with the exact solutions

Signal detection in extracellular neural ensemble recordings using higher criticism

Information processing in the brain is conducted by a concerted action of multiple neural populations. Gaining insights in the organization and dynamics of such populations can best be studied with broadband intracranial recordings of so-called extracellular field potential, reflecting neuronal spiking as well as mesoscopic activities, such as waves, oscillations, intrinsic large deflections, and multiunit spiking activity. Such signals are critical for our understanding of how neuronal ensembles encode sensory information and how such information is integrated in the large networks underlying cognition. The aforementioned principles are now well accepted, yet the efficacy of extracting information out of the complex neural data, and their employment for improving our understanding of neural networks, critically depends on the mathematical processing steps ranging from simple detection of action potentials in noisy traces - to fitting advanced mathematical models to distinct patterns of the neural signal potentially underlying intra-processing of information, e.g. interneuronal interactions. Here, we present a robust strategy for detecting signals in broadband and noisy time series such as spikes, sharp waves and multi-unit activity data that is solely based on the intrinsic statistical distribution of the recorded data. By using so-called higher criticism - a second-level significance testing procedure comparing the fraction of observed significances to an expected fraction under the global null - we are able to detect small signals in correlated noisy time-series without prior filtering, denoising or data regression. Results demonstrate the efficiency and reliability of the method and versatility over a wide range of experimental conditions and suggest the appropriateness of higher criticism to characterize neuronal dynamics without prior manipulation of the data

Calculating Iso-Committor Surfaces as Optimal Reaction Coordinates with Milestoning

Reaction coordinates are vital tools for qualitative and quantitative analysis of molecular processes. They provide a simple picture of reaction progress and essential input for calculations of free energies and rates. Iso-committor surfaces are considered the optimal reaction coordinate. We present an algorithm to compute efficiently a sequence of isocommittor surfaces. These surfaces are considered an optimal reaction coordinate. The algorithm analyzes Milestoning results to determine the committor function. It requires only the transition probabilities between the milestones, and not transition times. We discuss the following numerical examples: (i) a transition in the Mueller potential; (ii) a conformational change of a solvated peptide; and (iii) cholesterol aggregation in membranes

The Effects of L-Carnitine Supplementation on Serum Lipids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND: The findings of trials investigating the effects of L-carnitine administration on serum lipids are inconsistent. This meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effects of L-carnitine intake on serum lipids in patients and healthy individuals. METHODS: Two authors independently searched electronic databases including MEDLINE, EMBASE, Cochrane Library, Web of Science, PubMed and Google Scholar from 1990 until August 1, 2019, in order to find relevant RCTs. The quality of selected RCTs was evaluated using the Cochrane Collaboration risk of bias tool. Cochrane's Q test and I-square (I2) statistic were used to determine the heterogeneity across included trials. Weight mean difference (SMD) and 95 CI between the two intervention groups were used to determine pooled effect sizes. Subgroup analyses were performed to evaluate the source of heterogeneity based on suspected variables such as, participant's health conditions, age, dosage of L-carnitine, duration of study, sample size, and study location between primary RCTs. RESULTS: Out of 3460 potential papers selected based on keywords search, 67 studies met the inclusion criteria and were eligible for the meta-analysis. The pooled results indicated that L-carnitine administration led to a significant decrease in triglycerides (WMD: -10.35; 95 CI: -16.43, -4.27), total cholesterol (WMD: -9.47; 95 CI: - 13.23, -5.70) and LDL-cholesterol (LDL-C) concentrations (WMD: -6.25; 95 CI: -9.30, -3.21), and a significant increase in HDL-cholesterol (HDL-C) levels (WMD: 1.39; 95 CI: 0.21, 2.57). L-carnitine supplementation did not influence VLDL-cholesterol concentrations. When we stratified studies for the predefined factors such as dosage, and age, no significant effects of the intervention on triglycerides, LDL-C, and HDL-C levels were found. CONCLUSION: This meta-analysis demonstrated that L-carnitine administration significantly reduced triglycerides, total cholesterol and LDL-cholesterol levels, and significantly increased HDL-cholesterol levels in the pooled analyses, but did not affect VLDL-cholesterol levels; however, these findings were not confirmed in our subgroup analyses by participant's health conditions, age, dosage of L-carnitine, duration of study, sample size, and study location. Copyright© Bentham Science Publishers; For any queries, please email at [email protected]

A high-current, high-voltage power supply with special output current waveform for APS injector synchrotron dipole magnets

This paper describes a high-voltage, high-current power supply for the injector synchrotron dipole magnets at APS. In order to reset the dipole magnets in each cycle two different current waveforms are suggested. The first current waveform consists of three sections, namely: dc-reset, linear ramp, and recovery sections where injection is done on the fly''. The second current waveform consists of six different sections, dc-reset, transition to injection level, injection flat level, parabolic, linear ramp and recovery sections. The effect of such waveforms on the beam is discussed and the power supply limitations to follow such waveforms are given. The power supply limitations are due to the power components and control loops. The reference for the current loop is generated by a DAC which is discussed